Short answers, pulled from the story.
Elric of Melniboné was created by English writer Michael Moorcock. The character first appeared in print in the novella "The Dreaming City", published in Science Fantasy No. 47 in June 1961.
Stormbringer is a black sword that grants Elric strength, health, and fighting prowess, compensating for his physical weakness. It must feed on the souls of intelligent beings, and over the course of the stories it kills everyone close to Elric, including Elric himself in the end.
Moorcock cited Bertolt Brecht's Threepenny Novel and The Threepenny Opera as chief influences, dedicating the 1972 novel to Brecht. Poul Anderson's Three Hearts and Three Lions and Fletcher Pratt's The Well of the Unicorn were also named. Elric's albinism was directly influenced by Monsieur Zenith, an albino villain from the Sexton Blake stories written by Anthony Skene.
Deep Purple named their Stormbringer album after Elric's sword, and their 1984 track Perfect Strangers draws on the Elric stories. Hawkwind collaborated with Moorcock on multiple albums, most prominently the 1975 release Warrior on the Edge of Time and the 1985 album The Chronicle of the Black Sword. Blue Öyster Cult recorded the Moorcock-co-written song Black Blade for their 1980 album Cultösaurus Erectus.
Elric first appeared in large-circulation American comics in Conan the Barbarian issues 14-15 in 1972, written by Roy Thomas and illustrated by Barry Windsor-Smith. P. Craig Russell drew several adaptations for Pacific Comics, Epic Comics, and Dark Horse Comics from 1982 through 1998. A new French four-volume adaptation by Julien Blondel began with The Ruby Throne in 2014, with a second cycle starting in 2024.
Chaosium published the Stormbringer role-playing game set in Elric's Young Kingdoms, later releasing a revised version titled Elric! in 1993. After a dispute between Moorcock and Chaosium, Mongoose Publishing released a new version under their Runequest system in 2007. A French independent game called Black Sword Hack, released in 2020, gained notable attention within the Old School Renaissance movement.